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                    快速上手
            
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                    基础类型
            
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                    接口
            
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                    类
            
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                    函数
            
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                    泛型
            
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                    枚举
            
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                    类型推论
            
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                    类型兼容性
            
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                    高级类型
            
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                    实用工具类型
            
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                    Symbols
            
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                    Iterators 和 Generators
            
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                    模块
            
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                    命名空间
            
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                    命名空间和模块
            
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                    模块解析
            
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                    声明合并
            
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                    书写.d.ts文件
            
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                    JSX
            
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                    Decorators
            
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                    混入
            
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                    三斜线指令
            
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                    JavaScript文件里的类型检查
            
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                    如何书写声明文件
            
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                    结构
            
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                    规范
            
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                    举例
            
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                    深入
            
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                    发布
            
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                    使用
            
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                    工程配置
            
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                    tsconfig.json
            
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                    工程引用
            
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                    NPM包的类型
            
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        <li class="chapter " data-level="1.5.4" data-path="../handbook/Compiler Options.html">
            
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                    编译选项
            
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        <li class="chapter " data-level="1.5.5" data-path="../handbook/Configuring Watch.html">
            
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                    配置 Watch
            
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        <li class="chapter " data-level="1.5.6" data-path="../handbook/Compiler Options in MSBuild.html">
            
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                    在MSBuild里使用编译选项
            
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        <li class="chapter " data-level="1.5.7" data-path="../handbook/Integrating with Build Tools.html">
            
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                    与其它构建工具整合
            
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        <li class="chapter " data-level="1.5.8" data-path="../handbook/Nightly Builds.html">
            
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                    使用TypeScript的每日构建版本
            
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                    Wiki
            
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        <li class="chapter " data-level="1.6.1" data-path="../wiki/this-in-TypeScript.html">
            
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                    TypeScript里的this
            
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        <li class="chapter " data-level="1.6.2" data-path="../wiki/coding_guidelines.html">
            
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                    编码规范
            
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        <li class="chapter " data-level="1.6.3" data-path="../wiki/Common Errors.html">
            
                <a href="../wiki/Common Errors.html">
            
                    
                    常见编译错误
            
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        <li class="chapter " data-level="1.6.4" data-path="../wiki/TypeScript-Editor-Support.html">
            
                <a href="../wiki/TypeScript-Editor-Support.html">
            
                    
                    支持TypeScript的编辑器
            
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        <li class="chapter " data-level="1.6.5" data-path="../wiki/Using-TypeScript-With-ASP.NET-5.html">
            
                <a href="../wiki/Using-TypeScript-With-ASP.NET-5.html">
            
                    
                    结合ASP.NET v5使用TypeScript
            
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        <li class="chapter " data-level="1.6.6" data-path="../wiki/Architectural-Overview.html">
            
                <a href="../wiki/Architectural-Overview.html">
            
                    
                    架构概述
            
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        <li class="chapter " data-level="1.6.7" data-path="../wiki/Roadmap.html">
            
                <a href="../wiki/Roadmap.html">
            
                    
                    发展路线图
            
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            </ul>
            
        </li>
    
        <li class="chapter " data-level="1.7" data-path="../release-notes/">
            
                <a href="../release-notes/">
            
                    
                    新增功能
            
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        <li class="chapter " data-level="1.7.1" data-path="../release-notes/TypeScript 3.1.html">
            
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                    TypeScript 3.1
            
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        <li class="chapter " data-level="1.7.2" data-path="../release-notes/TypeScript 3.0.html">
            
                <a href="../release-notes/TypeScript 3.0.html">
            
                    
                    TypeScript 3.0
            
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        <li class="chapter " data-level="1.7.3" data-path="../release-notes/TypeScript 2.9.html">
            
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                    TypeScript 2.9
            
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        <li class="chapter " data-level="1.7.4" data-path="../release-notes/TypeScript 2.8.html">
            
                <a href="../release-notes/TypeScript 2.8.html">
            
                    
                    TypeScript 2.8
            
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        <li class="chapter " data-level="1.7.5" data-path="../release-notes/TypeScript 2.7.html">
            
                <a href="../release-notes/TypeScript 2.7.html">
            
                    
                    TypeScript 2.7
            
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        <li class="chapter " data-level="1.7.6" data-path="../release-notes/TypeScript 2.6.html">
            
                <a href="../release-notes/TypeScript 2.6.html">
            
                    
                    TypeScript 2.6
            
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        <li class="chapter " data-level="1.7.7" data-path="../release-notes/TypeScript 2.5.html">
            
                <a href="../release-notes/TypeScript 2.5.html">
            
                    
                    TypeScript 2.5
            
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        <li class="chapter " data-level="1.7.8" data-path="../release-notes/TypeScript 2.4.html">
            
                <a href="../release-notes/TypeScript 2.4.html">
            
                    
                    TypeScript 2.4
            
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        <li class="chapter " data-level="1.7.9" data-path="../release-notes/TypeScript 2.3.html">
            
                <a href="../release-notes/TypeScript 2.3.html">
            
                    
                    TypeScript 2.3
            
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        <li class="chapter " data-level="1.7.10" data-path="../release-notes/TypeScript 2.2.html">
            
                <a href="../release-notes/TypeScript 2.2.html">
            
                    
                    TypeScript 2.2
            
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        <li class="chapter " data-level="1.7.11" data-path="../release-notes/TypeScript 2.1.html">
            
                <a href="../release-notes/TypeScript 2.1.html">
            
                    
                    TypeScript 2.1
            
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        <li class="chapter " data-level="1.7.12" data-path="../release-notes/TypeScript 2.0.html">
            
                <a href="../release-notes/TypeScript 2.0.html">
            
                    
                    TypeScript 2.0
            
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        <li class="chapter " data-level="1.7.13" data-path="../release-notes/TypeScript 1.8.html">
            
                <a href="../release-notes/TypeScript 1.8.html">
            
                    
                    TypeScript 1.8
            
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        <li class="chapter " data-level="1.7.14" data-path="../release-notes/TypeScript 1.7.html">
            
                <a href="../release-notes/TypeScript 1.7.html">
            
                    
                    TypeScript 1.7
            
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        <li class="chapter " data-level="1.7.15" data-path="../release-notes/TypeScript 1.6.html">
            
                <a href="../release-notes/TypeScript 1.6.html">
            
                    
                    TypeScript 1.6
            
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        <li class="chapter " data-level="1.7.16" data-path="../release-notes/TypeScript 1.5.html">
            
                <a href="../release-notes/TypeScript 1.5.html">
            
                    
                    TypeScript 1.5
            
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        <li class="chapter " data-level="1.7.17" data-path="../release-notes/TypeScript 1.4.html">
            
                <a href="../release-notes/TypeScript 1.4.html">
            
                    
                    TypeScript 1.4
            
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        <li class="chapter " data-level="1.7.18" data-path="../release-notes/TypeScript 1.3.html">
            
                <a href="../release-notes/TypeScript 1.3.html">
            
                    
                    TypeScript 1.3
            
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        <li class="chapter " data-level="1.7.19" data-path="../release-notes/TypeScript 1.1.html">
            
                <a href="../release-notes/TypeScript 1.1.html">
            
                    
                    TypeScript 1.1
            
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            </ul>
            
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        <li class="chapter " data-level="1.8" data-path="breaking-changes.html">
            
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                    Breaking Changes
            
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        <li class="chapter " data-level="1.8.1" data-path="TypeScript 2.4.html">
            
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                    TypeScript 2.4
            
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        <li class="chapter " data-level="1.8.2" data-path="TypeScript 2.3.html">
            
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                    TypeScript 2.3
            
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        <li class="chapter " data-level="1.8.3" data-path="TypeScript 2.2.html">
            
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                    TypeScript 2.2
            
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        <li class="chapter " data-level="1.8.4" data-path="TypeScript 2.1.html">
            
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                    TypeScript 2.1
            
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        <li class="chapter " data-level="1.8.5" data-path="TypeScript 2.0.html">
            
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                    TypeScript 2.0
            
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        <li class="chapter " data-level="1.8.6" data-path="TypeScript 1.8.html">
            
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                    TypeScript 1.8
            
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        <li class="chapter active" data-level="1.8.7" data-path="TypeScript 1.7.html">
            
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                                <h1 id="typescript-17">TypeScript 1.7</h1>
<p>&#x5B8C;&#x6574;&#x7684;&#x7834;&#x574F;&#x6027;&#x6539;&#x52A8;&#x5217;&#x8868;&#x8BF7;&#x5230;&#x8FD9;&#x91CC;&#x67E5;&#x770B;:<a href="https://github.com/Microsoft/TypeScript/issues?q=is%3Aissue+milestone%3A%22TypeScript+1.7%22+label%3A%22breaking+change%22" target="_blank">breaking change issues</a>&#x3002;</p>
<h4 id="&#x4ECE;this&#x4E2D;&#x63A8;&#x65AD;&#x7C7B;&#x578B;&#x53D1;&#x751F;&#x4E86;&#x53D8;&#x5316;">&#x4ECE;<code>this</code>&#x4E2D;&#x63A8;&#x65AD;&#x7C7B;&#x578B;&#x53D1;&#x751F;&#x4E86;&#x53D8;&#x5316;</h4>
<p>&#x5728;&#x7C7B;&#x91CC;&#xFF0C;<code>this</code>&#x503C;&#x7684;&#x7C7B;&#x578B;&#x5C06;&#x88AB;&#x63A8;&#x65AD;&#x6210;<code>this</code>&#x7C7B;&#x578B;&#x3002;
&#x8FD9;&#x610F;&#x5473;&#x7740;&#x968F;&#x540E;&#x4F7F;&#x7528;&#x539F;&#x59CB;&#x7C7B;&#x578B;&#x8D4B;&#x503C;&#x65F6;&#x53EF;&#x80FD;&#x4F1A;&#x53D1;&#x751F;&#x9519;&#x8BEF;&#x3002;</p>
<p><strong>&#x4F8B;&#x5B50;&#xFF1A;</strong></p>
<pre><code class="lang-TypeScript"><span class="hljs-keyword">class</span> Fighter {
    <span class="hljs-comment">/** @returns the winner of the fight. */</span>
    fight(opponent: Fighter) {
        <span class="hljs-keyword">let</span> theVeryBest = <span class="hljs-keyword">this</span>;
        <span class="hljs-keyword">if</span> (<span class="hljs-built_in">Math</span>.rand() &lt; <span class="hljs-number">0.5</span>) {
            theVeryBest = opponent; <span class="hljs-comment">// error</span>
        }
        <span class="hljs-keyword">return</span> theVeryBest
    }
}
</code></pre>
<p><strong>&#x63A8;&#x8350;&#xFF1A;</strong></p>
<p>&#x6DFB;&#x52A0;&#x7C7B;&#x578B;&#x6CE8;&#x89E3;&#xFF1A;</p>
<pre><code class="lang-TypeScript"><span class="hljs-keyword">class</span> Fighter {
    <span class="hljs-comment">/** @returns the winner of the fight. */</span>
    fight(opponent: Fighter) {
        <span class="hljs-keyword">let</span> theVeryBest: Fighter = <span class="hljs-keyword">this</span>;
        <span class="hljs-keyword">if</span> (<span class="hljs-built_in">Math</span>.rand() &lt; <span class="hljs-number">0.5</span>) {
            theVeryBest = opponent; <span class="hljs-comment">// no error</span>
        }
        <span class="hljs-keyword">return</span> theVeryBest
    }
}
</code></pre>
<h4 id="&#x7C7B;&#x6210;&#x5458;&#x4FEE;&#x9970;&#x7B26;&#x540E;&#x9762;&#x4F1A;&#x81EA;&#x52A8;&#x63D2;&#x5165;&#x5206;&#x53F7;">&#x7C7B;&#x6210;&#x5458;&#x4FEE;&#x9970;&#x7B26;&#x540E;&#x9762;&#x4F1A;&#x81EA;&#x52A8;&#x63D2;&#x5165;&#x5206;&#x53F7;</h4>
<p>&#x5173;&#x952E;&#x5B57;<code>abstract&#xFF0C;public&#xFF0C;protected</code>&#x548C;<code>private</code>&#x662F;ECMAScript 3&#x91CC;&#x7684;<em>&#x4FDD;&#x7559;&#x5173;&#x952E;&#x5B57;</em>&#x5E76;&#x9002;&#x7528;&#x4E8E;&#x81EA;&#x52A8;&#x63D2;&#x5165;&#x5206;&#x53F7;&#x673A;&#x5236;&#x3002;
&#x4E4B;&#x524D;&#xFF0C;&#x5728;&#x8FD9;&#x4E9B;&#x5173;&#x952E;&#x5B57;&#x51FA;&#x73B0;&#x7684;&#x884C;&#x5C3E;&#xFF0C;TypeScript&#x662F;&#x4E0D;&#x4F1A;&#x63D2;&#x5165;&#x5206;&#x53F7;&#x7684;&#x3002;
&#x73B0;&#x5728;&#xFF0C;&#x8FD9;&#x5DF2;&#x7ECF;&#x88AB;&#x6539;&#x6B63;&#x4E86;&#xFF0C;&#x5728;&#x4E0A;&#x4F8B;&#x4E2D;<code>abstract class D</code>&#x4E0D;&#x518D;&#x80FD;&#x591F;&#x6B63;&#x786E;&#x5730;&#x7EE7;&#x627F;<code>C</code>&#x4E86;&#xFF0C;&#x800C;&#x662F;&#x58F0;&#x660E;&#x4E86;&#x4E00;&#x4E2A;<code>m</code>&#x65B9;&#x6CD5;&#x548C;&#x4E00;&#x4E2A;&#x989D;&#x5916;&#x7684;&#x5C5E;&#x6027;<code>abstract</code>&#x3002;</p>
<p>&#x6CE8;&#x610F;&#xFF0C;<code>async</code>&#x548C;<code>declare</code>&#x5DF2;&#x7ECF;&#x80FD;&#x591F;&#x6B63;&#x786E;&#x81EA;&#x52A8;&#x63D2;&#x5165;&#x5206;&#x53F7;&#x4E86;&#x3002;</p>
<p><strong>&#x4F8B;&#x5B50;&#xFF1A;</strong></p>
<pre><code class="lang-TypeScript"><span class="hljs-keyword">abstract</span> <span class="hljs-keyword">class</span> C {
    <span class="hljs-keyword">abstract</span> m(): <span class="hljs-built_in">number</span>;
}
<span class="hljs-keyword">abstract</span> <span class="hljs-keyword">class</span> D extends C {
    <span class="hljs-keyword">abstract</span>
    m(): <span class="hljs-built_in">number</span>;
}
</code></pre>
<p><strong>&#x63A8;&#x8350;&#xFF1A;</strong></p>
<p>&#x5728;&#x5B9A;&#x4E49;&#x7C7B;&#x6210;&#x5458;&#x65F6;&#x5220;&#x9664;&#x5173;&#x952E;&#x5B57;&#x540E;&#x9762;&#x7684;&#x6362;&#x884C;&#x3002;&#x901A;&#x5E38;&#x6765;&#x8BB2;&#xFF0C;&#x8981;&#x907F;&#x514D;&#x4F9D;&#x8D56;&#x4E8E;&#x81EA;&#x52A8;&#x63D2;&#x5165;&#x5206;&#x53F7;&#x673A;&#x5236;&#x3002;</p>

                                
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